The study started as an accident. Geneticist Patricia Hunt of Washington State University and her team were investigating the reproductive effects of BPA in mice. Housed in BPA-free plastic cages, the test group got doses of BPA through a dropper; the control group didn't.plastic cosmetic storage boxes
Our control data just started to get really wonky,” Hunt says. The differences between it and the test group vanished, and many control mice started showing genetic issues. Though initially confused, the team discovered that some of the plastic caging was damaged and was leaching bisphenol S, or BPS—an alternative to the now infamous plastic component BPA.
It was like déjà vu, Hunt says. Twenty years ago, she’d had the same issue with BPA in polycarbonate mouse cages. Now her study of the effects of several BPA alternatives, prompted by the latest accidental findings, suggests that these replacements impact reproduction in mice in much the same way.
Of course, it's hard to draw conclusions between the effects in these tiny furry critters and those in our comparatively massive fleshy forms, but the latest work adds to a growing body of evidence that suggests all is not safe in the world of BPA-free plastics. What's more, the study underlines a broader issue in commercial compound development: When chemicals are removed from the market, they're often replaced by others that not only look similar—but act similarly in our bodies.
“We have to play catch up as disease detectives,” says Leonardo Trasande, director of the division of environmental pediatrics at NYU Langone Health, who was not involved in the research. But this detective work is a losing proposition, he says likening it to a game of “chemical whack-a-mole.”